///
///    This file is part of ILNumerics Community Edition.
///
///    ILNumerics Community Edition - high performance computing for applications.
///    Copyright (C) 2006 - 2012 Haymo Kutschbach, http://ilnumerics.net
///
///    ILNumerics Community Edition is free software: you can redistribute it and/or modify
///    it under the terms of the GNU General Public License version 3 as published by
///    the Free Software Foundation.
///
///    ILNumerics Community Edition is distributed in the hope that it will be useful,
///    but WITHOUT ANY WARRANTY; without even the implied warranty of
///    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
///    GNU General Public License for more details.
///
///    You should have received a copy of the GNU General Public License
///    along with ILNumerics Community Edition. See the file License.txt in the root
///    of your distribution package. If not, see <http://www.gnu.org/licenses/>.
///
///    In addition this software uses the following components and/or licenses: 
///
///    =================================================================================
///    The Open Toolkit Library License
///    
///    Copyright (c) 2006 - 2009 the Open Toolkit library.
///    
///    Permission is hereby granted, free of charge, to any person obtaining a copy
///    of this software and associated documentation files (the "Software"), to deal
///    in the Software without restriction, including without limitation the rights to 
///    use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
///    the Software, and to permit persons to whom the Software is furnished to do
///    so, subject to the following conditions:
///
///    The above copyright notice and this permission notice shall be included in all
///    copies or substantial portions of the Software.
///
///    =================================================================================
///    

using System;
using System.Collections.Generic;
using System.Text;
using ILNumerics;
using ILNumerics.Exceptions;
using ILNumerics.Storage;
using ILNumerics.Misc;

namespace ILNumerics {
    public partial class ILMath {
        /// <summary>
        /// Convert sequential index into subscript indices
        /// </summary>
        /// <param name="A">Input array</param>
        /// <param name="seqindex">Sequential index</param>
        /// <returns>Subscript indices</returns>
        /// <remarks><para>The index array returned will have the length of number of dimensions of A</para>
        /// <para>If A is a null or an empty array, the return value will be also be empty</para>
        /// </remarks>
        /// <exception cref="System.IndexOutOfRangeException">If seqindex is &lt; 0 or &gt;= numel(A)</exception>
        public static ILRetArray<double> ind2sub(ILBaseArray A, int seqindex) {
            using (ILScope.Enter(A)) {
                if (object.Equals(A, null) || A.IsEmpty)
                    return empty();
                if (seqindex < 0 || seqindex >= A.Size.NumberOfElements)
                    throw new ILArgumentException("index out of range: " + seqindex);
                int IdxCpy = seqindex;
                ILArray<double> ret = zeros(1, A.Size.NumberOfDimensions);
                for (int d = 0; d < ret.Length; d++) {
                    ret.SetValue(IdxCpy % A.Size[d], d);
                    IdxCpy /= A.Size[d];
                }
                return ret;
            }
        }
    }
}